Manufacture of ornamental or effect materials



Patented Sept; "13,119 27;

UNITED STATES PATENT OFFICE.-

DERBY, ENGLAND, IPORATION OF DELAWARE.

WILLIAM ALEXANDER DIGKIE AND JAMES- HENRY nooNEY, or sPoNDoN, NEAR ASSIGNORS T0 CELANESE conroan'rron or AMERICA, A con- MANUFACTURE OF ORNAMENTAL 0R EFFECT MATERIALS:

No Drawing. Application filed February 2, 1925, Serial No. 6,457, and in This invention relates to the manufacture of new materials presenting 'moir efi'ects visible by transmitted light.

'We produce said materials by impressing close line patterns or grid patterns in or on the opposite faces of thin or relatively thin sheets, bands or the like of a light transmitting that is, to say, transparent or translucent plastic material, so that optical interference effects'are created by the lines on the two faces. By this means we have found thatexcellent moire-like effects can be obtained on the sheets, bands or the like when viewed by transmitted light.

The invention is applicable to transparent or translucent sheets, bands or the like of any suitable plastic materials capable of being impressed with the line or grid patterns, for instance celluloid or celluloid substitutes, and especially to sheets, bands, etc., of material consisting or having a basis of cellulose acetate, ethyl-, methylor benzylcellulose or other low flammable cellulose derivatives- Such materials, as is known usually contain plasticizing or softening agents in their composition.

The lines or grids on the opposite faces of the sheets, bands etc. are generally slightly out of register to produce the interference efi'ect.

The line or grid patterns may be impressed in or upon the faces of the sheets, bands, etc. in any suitable or convenient way, for example by closely arranged parallel fine wires, or 'by means of fine wire gauze, or by means of plates, rollers or other devices engraved, etched or scored with the line or grid pattern, or in any other suitable way, the degrees of fineness and closeness of the lines or grids governing the effect or result obtained. It is understood that the lines may be straight or curved and may or may not form a grid pattern.

In carrying out the invention we may for example employ as impressing means metal sheets or plates covered on one side with tough, finely woven wire gauze, preferably of phosphor bronze, the number 'of meshes and fineness of wire depending upon the effect desired and governing the result obtained. As an instance only, we may employ a fine wire gauze of about 140 meshes.

per inch. Conveniently the auzes may be soldered or brazed at the en s only to the g the gauze and, the

cold water.

Great Britain January '14, 1925.

metal sheets, allowing room for a pad of a number of thicknesses of paper between plate, in order to take up inequalities and distribute heat and pressure in the impressing operation. Or the plates themselves may be ruled by engine dividing or otherwise provided withv a slightly incised close line or grid pattern- Or accordingto another way we may employ plates made by first preparing an impression of the line or grid pattern on gutta percha, rubbing on graphite and electroplating a solid plate on to the graphite. Or we may prepare plates by protecting the face of a wire gauze with acid resisting, electrically insulating varnish and then electroplating.a solid metal plate at the back of the gauze, the varnish being then removed from the gauze thus united or attached tothe metal backing.

The following is one example of the manner in which the invention may be performed in practice, it being understood that this is given only by way of illustration and may be varied widely without departing from the invention. 1

Transparent or translucent sheets of a plastic material such as cellulose acetate or celluloid sheeting, polished or not, are disposed each between two plates prepared in any of the ways before indicated or in any other suitable way for impressing the .required line or grid pattern. The pairs of plates with the sheets between are placed in an hydraulic press each between platens provided with steam heating and water cooling means and are subjected at a suitable temperature for instance about 100- C. to pressure, to impress the line or grid pattern in or on the faces of the sheets of plastic material.

The heat and pressure and duration of same may vary according to the thicknessof the material ofthe sheets. For example for cellulose acetate sheeting "or celluloid sheeting about ten thousandths of an inch thick, pressure of about 500 pounds per square inch of the surface of the sheet may be maintained for about two minutes. he platens are then cooled rapidly by a How of Cooling takes place under the pressure and the sheets'are then removed from the press.

The disposition of the-plates, fineness of line or grid pattern impressed, and thiclrness of sheet, produces for each variant a ditlerent moire edect.

It is understood that the line or grid patterns may be impressed in or on the sheets, bands or the like in any other appropriate way than that just described. for instance by means of any other suitable press or by heated rollers engraved on otherwise adapted to impress the line or grid pattern.

By means of the invention materials can be produced presenting permanent moir eilects and suitable for decorative worlr, lamp shades, screens and many other uses.

It is to he understood that in the claims the term sheet includes bands or similar construct-ions.

What we claim and desire to secure by Letters Patent is 1. A new article of manufacture comprising a sheet of light transmitting material having on its opposite surfaces close line or grid patterns in conformation and presenting moire effects.

2. A new article of manufacture comprising a sheet of light transmitting material comprising a low flammable derivative of cellulose having on its opposite surfaces close line or grid patterns in conformation and presenting moir effects.

3. A new article of manufacture comprising a sheet of light transmitting material comprising a cellulose ester having on its opposite surfaces close line or grid patterns in conformation and presenting moir effects. 4. A new article of manufacture comprismg a sheet of light transmitting material rat-race comprising cellulose acetate having on its opposite surfaces close line or grid patterns in conformation and presenting moir e-f tects.

5. A process for manufacturing a material presenting moir effects which comprises forming close line or grid patterns on the opposite surface of a sheet of light transmitting material.

6. A process for manufacturing a material presenting moire eflects which comprises impressing close line or grid patterns on the opposite surface of a sheet of light transmitting material comprising a low flammable derivative of cellulose.

7. A process for manufacturing a material presenting moir effects which comprises impressing close line or grid patterns on the opposite surface of a sheet of light transmitting material comprising a cellulose ester. i

8. A process for manufacturing a material presenting rnoir ellects which comprises impressing-close line or grid patterns on the opposite surface of a-sheet of light transmitting material comprising cellulose acetate.

9. A process for manufacturing a mate rial presenting moir effects which comprises impressing, by means of heat and pressure, close line or grid patterns on the opposite surfaces of a sheet of light transmitting material comprising a low flammable derivative of cellulose.

In testimony whereof we have hereunto subscribed our names.

WILLIAM ALEXANDER DICKIE. JAMES HENRY RODNEY. 

